Light Burn/ Phosphorus deficiency?

[DDubs]

Thanks for all the great info in the forum. I'm in my second grow and trying to avoid the same pitfalls as last time. I definitely light burned, stunted and screwed up the cure process with my last girl.


-Problem: Damaged fan leaves when I switched on both the veg and bloom lights. I have been running just the veg light to this point. With the light set at 24" I used my PAR meter and found that with the veg light I get about 320 mols and with both veg and bloom I get about 840 mols. So after watching the lighting video and reading up, that I should be able to run full lights if I can dial everything else in.

-Medium/grow method: Michigan Made Mix soil .0015-.0033-.0038

-Feed and supplements used: MaxiBloom 5:15:14 I just started giving 1/4 dose every other watering (2-3 days). I dont water to get runoff just enough to soak the soil.

-Water source: I use rain water runoff with a ph just under 7. Measured with a cheezy probe. I admittedly should get a decent meter but I just bought the PAR meter so, one thing at a time.

-Strain and age Tangie Dream Auto 42 days into veg. My last grow went 120+ days.

-Climate: 44%-73% RH and 60-70 degrees. Only extrem exposure was turning the lights on full power. I have a mini dehumidifier and was planning on getting a mini humidifier as well. I was worried about over loafing the tent.

- Light used: Running Topolite LED's. Product data sheet listed at 600w - 240w actual. Wave length 380-800nm. Lights on 20/4. Held up between 18"-24" from tops.

-Additional info: A couple spots appeared on older fan leaves a couple hours after I turn on both the veg and bloom lights. They got worse after I turned the bloom back off but have started to look a little better. I did dump a bunch of 1/4 dose nutrient water on the other day.

--Pictures

 

[Mañ'O'Green]

@DDubsWelcome to AFN.

What kind of PAR meter did you get because a 240w light with 840 Moles does not add up. The light looks to be too heavy blue and is too far from the plant IMPO.

How are you catching your rain water?

60°F to 70°F is too cold and appears to be stunting the growth you want to shoot for 68°F to 78°F.

Looks like too much something is locking out P-K

Take a look here:

Tutorial - A word on Nutrients

The proper use of “salt” based fertilizer to grow Auto Flowering Cannabis. Salts: Natural and man made any chemical compound formed from the reaction of an acid with a base, with all or part of the hydrogen of the acid replaced by a metal or other cation. Learning how to use salt based...

www.autoflower.org

Are you sure that is an auto?

 

[DDubs]

Thanks for the reply ManO. Sorry for the delay. After I reread my post came up with more questions that I needed to answer before I can talk somewhat intelligently about what going on.

The picture was a progress photo and not with both the veg and bloom lights on. It might look at little small because I topped it above the 5th node so I have 10 branches to work with. I ended up buying the Quantum PAR meter that measures between 400-700nm. Reading up on it, people say it's about 50mols off on the readings. I rechecked the reading based on where I'm at right now. I get about 830 at the top and 430 at the base of the plant.

I was capturing water from a flat rubber roof. I bought a new pH meter and found that it was at 6.3. I went through and measured a few other sources. I found that my tap water, after sitting for 24 hours is at 7.2. I already watered so I didnt want to over water just to find my runoff rate. I'll water it to runoff in a day or two to see where I'm at. I'm just wondering what to water with? I was thinking of using some settled tap water to see what I get.

With both the veg and bloom lights on, the tent is at 75 degrees and 50%-60% RH.

I have been watering with the roof water and I'm thinking the pH is too low as it makes it way through the soil. She started flowering the other day, so do or die, she's going for the gold.

 

[DDubs]

I flushed the pot with 1/4 dose of nutrients and 6.5 pH water. The runoff was as 6.7 so I'm guessing I was in the high 6's before the flush. Hopefully I see some improvement over the next couple days. She's looking sad right now.